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A Study to Learn About the Medicine (PF-07321332 or Nirmatrelvir/Ritonavir) in Healthy Lactating Women

The safety and scientific validity of this study is the responsibility of the study sponsor and investigators. Listing a study does not mean it has been evaluated by the U.S. Federal Government. Know the risks and potential benefits of clinical studies and talk to your health care provider before participating. Read our disclaimer for details.
 
ClinicalTrials.gov Identifier: NCT05441215
Recruitment Status : Recruiting
First Posted : July 1, 2022
Last Update Posted : March 13, 2023
Sponsor:
Information provided by (Responsible Party):
Pfizer

Study Description
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Brief Summary:

The main purpose of this study is to measure the level of active ingredient of the study medicine (nirmatrelvir) that is secreted in human breast milk when it is given to healthy breastfeeding women. The study medicine consists of two medicines, nirmatrelvir and ritonavir. We are seeking female participants who are:

  • Actively breast-feeding (lactating) at least 12 weeks postpartum;
  • Age between 18 to 55 years and not currently pregnant;
  • Have a Body Mass Index (BMI): 17.5 kg/m2; and a total body weight >50 kg (110 lb).

Participants will take the study medicine by mouth for a total of 3 times over 2 days (2 morning doses and 1 evening dose) at the study clinic. We will periodically collect breast milk from day 2 to 4 to measure the level of nirmatrelvir and ritonavir in it. A safety follow up call will be conducted around 28-35 days from the last dose to monitor any reactions participants may have to the study medicine.


Condition or disease Intervention/treatment Phase
Healthy Participants Drug: nirmatrelvir Drug: ritonavir Phase 1

Study Design
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Study Type : Interventional  (Clinical Trial)
Estimated Enrollment : 8 participants
Allocation: N/A
Intervention Model: Single Group Assignment
Masking: None (Open Label)
Primary Purpose: Other
Official Title: A PHASE I, MULTIPLE DOSE, OPEN-LABEL PHARMACOKINETIC STUDY OF NIRMATRELVIR/RITONAVIR IN HEALTHY LACTATING WOMEN
Actual Study Start Date : December 12, 2022
Estimated Primary Completion Date : September 7, 2023
Estimated Study Completion Date : September 7, 2023

Resource links provided by the National Library of Medicine


Arms and Interventions
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Arm Intervention/treatment
Experimental: nirmatrelvir/ritonavir
nirmatrelvir/ritonavir will be given by mouth two times a day as a tablet
 Drug: nirmatrelvir
nirmatrelvir/ritonavir
Other Name: PF-07321332/ritonavir

Drug: ritonavir
nirmatrelvir/ritonavir
Other Name: PF-07321332/ritonavir


Outcome Measures
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Primary Outcome Measures :
  1. Maximum Breastmilk Concentration (Cmax) of nirmatrelvir [ Time Frame: Day 2 (0, 0.5, 1, 2, 3, 4, 6, 8, 10, 12 hours) and Day 3 (18, 24, 32, 40 hours) Day 4 (48 hours) ]
  2. Time to Reach Maximum Breastmilk Concentration (Tmax) of nirmatrelvir [ Time Frame: Day 2 (0, 0.5, 1, 2, 3, 4, 6, 8, 10, 12 hours) and Day 3 (18, 24, 32, 40 hours) Day 4 (48 hours) ]
  3. Area under the breastmilk concentration time profile from time 0 to the time of the end of the dosing interval (tau) of nirmatrelvir [ Time Frame: Day 2 (0, 0.5, 1, 2, 3, 4, 6, 8, 10, 12 hours) and Day 3 (18, 24, 32, 40 hours) Day 4 (48 hours) ]
  4. Terminal phase half life (t½) of nirmatrelvir [ Time Frame: Day 2 (0, 0.5, 1, 2, 3, 4, 6, 8, 10, 12 hours) and Day 3 (18, 24, 32, 40 hours) Day 4 (48 hours) ]
  5. Average breastmilk concentration (Cav) of nirmatrelvir [ Time Frame: Day 2 (0, 0.5, 1, 2, 3, 4, 6, 8, 10, 12 hours) and Day 3 (18, 24, 32, 40 hours) Day 4 (48 hours) ]
  6. Amount excreted in breast milk over the dosing interval (Aetau) of nirmatrelvir [ Time Frame: Day 2 (0, 0.5, 1, 2, 3, 4, 6, 8, 10, 12 hours) and Day 3 (18, 24, 32, 40 hours) Day 4 (48 hours) ]
  7. Percent of dose excreted in breast milk during the dosing interval (Aetau %) of nirmatrelvir [ Time Frame: Day 2 (0, 0.5, 1, 2, 3, 4, 6, 8, 10, 12 hours) and Day 3 (18, 24, 32, 40 hours) Day 4 (48 hours) ]
  8. Breast milk clearance (CLbm) of nirmatrelvir [ Time Frame: Day 2 (0, 0.5, 1, 2, 3, 4, 6, 8, 10, 12 hours) and Day 3 (18, 24, 32, 40 hours) Day 4 (48 hours) ]

Secondary Outcome Measures :
  1. Cmax of ritonavir [ Time Frame: Day 2 (0, 0.5, 1, 2, 3, 4, 6, 8, 10, 12 hours) and Day 3 (18, 24, 32, 40 hours) Day 4 (48 hours) ]
  2. Tmax of ritonavir [ Time Frame: Day 2 (0, 0.5, 1, 2, 3, 4, 6, 8, 10, 12 hours) and Day 3 (18, 24, 32, 40 hours) Day 4 (48 hours) ]
  3. Area under the breastmilk concentration time profile from time 0 to the time of the end of the dosing interval (Auc tau) of ritonavir [ Time Frame: Day 2 (0, 0.5, 1, 2, 3, 4, 6, 8, 10, 12 hours) and Day 3 (18, 24, 32, 40 hours) Day 4 (48 hours) ]
  4. t½ of ritonavir [ Time Frame: Day 2 (0, 0.5, 1, 2, 3, 4, 6, 8, 10, 12 hours) and Day 3 (18, 24, 32, 40 hours) Day 4 (48 hours) ]
  5. Cav of ritonavir [ Time Frame: Day 2 (0, 0.5, 1, 2, 3, 4, 6, 8, 10, 12 hours) and Day 3 (18, 24, 32, 40 hours) Day 4 (48 hours) ]
  6. Aetau of ritonavir [ Time Frame: Day 2 (0, 0.5, 1, 2, 3, 4, 6, 8, 10, 12 hours) and Day 3 (18, 24, 32, 40 hours) Day 4 (48 hours) ]
  7. Aetau % of ritonavir [ Time Frame: Day 2 (0, 0.5, 1, 2, 3, 4, 6, 8, 10, 12 hours) and Day 3 (18, 24, 32, 40 hours) Day 4 (48 hours) ]
  8. CLbm of ritonavir [ Time Frame: Day 2 (0, 0.5, 1, 2, 3, 4, 6, 8, 10, 12 hours) and Day 3 (18, 24, 32, 40 hours) Day 4 (48 hours) ]
  9. Cmax of nirmatrelvir and ritonavir [ Time Frame: Day 2 (0, 0.5, 1, 2, 3, 4, 6, 8, 10, 12 hours) and Day 3 (18, 24, 32, 40 hours) Day 4 (48 hours) ]
  10. Cav of nirmatrelvir and ritonavir [ Time Frame: Day 2 (0, 0.5, 1, 2, 3, 4, 6, 8, 10, 12 hours) and Day 3 (18, 24, 32, 40 hours) Day 4 (48 hours) ]
  11. Pre-dose concentration (Ctrough) of nirmatrelvir and ritonavir [ Time Frame: Day 2 (0, 0.5, 1, 2, 3, 4, 6, 8, 10, 12 hours) and Day 3 (18, 24, 32, 40 hours) Day 4 (48 hours) ]
  12. Tmax of nirmatrelvir and ritonavir [ Time Frame: Day 2 (0, 0.5, 1, 2, 3, 4, 6, 8, 10, 12 hours) and Day 3 (18, 24, 32, 40 hours) Day 4 (48 hours) ]
  13. AUC tau of nirmatrelvir and ritonavir [ Time Frame: Day 2 (0, 0.5, 1, 2, 3, 4, 6, 8, 10, 12 hours) and Day 3 (18, 24, 32, 40 hours) Day 4 (48 hours) ]
  14. Minimum Observed Breastmilk Concentration (Cmin) of nirmatrelvir and ritonavir [ Time Frame: Day 2 (0, 0.5, 1, 2, 3, 4, 6, 8, 10, 12 hours) and Day 3 (18, 24, 32, 40 hours) Day 4 (48 hours) ]
  15. t½ of nirmatrelvir and ritonavir [ Time Frame: Day 2 (0, 0.5, 1, 2, 3, 4, 6, 8, 10, 12 hours) and Day 3 (18, 24, 32, 40 hours) Day 4 (48 hours) ]
  16. Apparent plasma clearance (CL/F) of nirmatrelvir and ritonavir [ Time Frame: Day 2 (0, 0.5, 1, 2, 3, 4, 6, 8, 10, 12 hours) and Day 3 (18, 24, 32, 40 hours) Day 4 (48 hours) ]
  17. Apparent volume of distribution (Vz/F) of nirmatrelvir and ritonavir [ Time Frame: Day 2 (0, 0.5, 1, 2, 3, 4, 6, 8, 10, 12 hours) and Day 3 (18, 24, 32, 40 hours) Day 4 (48 hours) ]
  18. Daily (24 hour) amount of nirmatrelvir excreted in breast milk (Ae 24bm) [ Time Frame: Day 2 (0, 0.5, 1, 2, 3, 4, 6, 8, 10, 12 hours) and Day 3 (18, 24, 32, 40 hours) Day 4 (48 hours) ]
  19. Breast milk to plasma ratio for AUC tau (MPAUC tau) for both nirmatrelvir and ritonavir [ Time Frame: Day 2 (0, 0.5, 1, 2, 3, 4, 6, 8, 10, 12 hours) and Day 3 (18, 24, 32, 40 hours) Day 4 (48 hours) ]
  20. Breast milk to plasma ratio for AUC tau (MPCmax during dosing interval tau) for both nirmatrelvir and ritonavir [ Time Frame: Day 2 (0, 0.5, 1, 2, 3, 4, 6, 8, 10, 12 hours) and Day 3 (18, 24, 32, 40 hours) Day 4 (48 hours) ]
  21. CLbm for both nirmatrelvir and ritonavir [ Time Frame: Day 2 (0, 0.5, 1, 2, 3, 4, 6, 8, 10, 12 hours) and Day 3 (18, 24, 32, 40 hours) Day 4 (48 hours) ]
  22. Milk to plasma ratio (M/P) of both nirmatrelvir and ritonavir [ Time Frame: Day 2 (0, 0.5, 1, 2, 3, 4, 6, 8, 10, 12 hours) and Day 3 (18, 24, 32, 40 hours) Day 4 (48 hours) ]
  23. Body weight normalized infant dose in μg/kg/day (BWNID) of both nirmatrelvir and ritonavir [ Time Frame: Day 2 (0, 0.5, 1, 2, 3, 4, 6, 8, 10, 12 hours) and Day 3 (18, 24, 32, 40 hours) Day 4 (48 hours) ]
  24. Body weight normalized maternal dose in μg/kg/day (BWNMD) of both nirmatrelvir and ritonavir [ Time Frame: Day 2 (0, 0.5, 1, 2, 3, 4, 6, 8, 10, 12 hours) and Day 3 (18, 24, 32, 40 hours) Day 4 (48 hours) ]
  25. Infant dose expressed as % of body weight normalized maternal dose (BWNIDPCM) of both nirmatrelvir and ritonavir [ Time Frame: Day 2 (0, 0.5, 1, 2, 3, 4, 6, 8, 10, 12 hours) and Day 3 (18, 24, 32, 40 hours) Day 4 (48 hours) ]
  26. Participants reporting treatment emergent adverse events [ Time Frame: Baseline to 28 days after last dose ]
  27. Participants reporting abnormal clinical laboratory lab tests [ Time Frame: Baseline to 28 days after last dose ]
  28. Participants reporting abnormal vital signs [ Time Frame: Baseline to 28 days after last dose ]
  29. Participants reporting abnormal physical examination results [ Time Frame: Baseline to 28 days after last dose ]
  30. Participants reporting abnormal electrocardiograms [ Time Frame: Baseline to 28 days after last dose ]

Eligibility Criteria
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Ages Eligible for Study:   18 Years to 55 Years   (Adult)
Sexes Eligible for Study:   Female
Gender Based Eligibility:   Yes
Gender Eligibility Description:   Healthy lactating women
Accepts Healthy Volunteers:   Yes
Criteria

Inclusion Criteria:

  • Healthy lactating females who are actively breast-feeding or expressing breast milk, at least 12 weeks post-partum and not currently pregnant between 18 and 55 years old
  • Body Mass Index (BMI): 17.5 kg/m2; and a total body weight >50 kg (110 lb)
  • Infants of women enrolled in the study must be able to feed successfully from a bottle or other age-appropriate alternative feeding method prior to the start of the study and must be able to tolerate infant formula if the mother does not have a supply of stored breast milk sufficient to cover the duration of the study
  • Participants must be willing to temporarily discontinue breast feeding their infants for a total of 4.5 days (108 hours)
  • Participants must be willing to regularly pump breasts throughout the study and express milk according to a schedule designed to maintain lactation throughout the study period

Exclusion Criteria:

  • Positive test result (RT-PCR) for SARS-CoV-2 infection at the time of screening or Day -1
  • Evidence or history of clinically significant findings
  • History of febrile illness or mastitis within 5 days prior to the first dose of study medication
  • Participants who have received a COVID-19 vaccine within 7 days before screening or admission, or who are to be vaccinated with a COVID-19 vaccine at any time during the study confinement period
  • History of HIV infection, hepatitis B, or hepatitis C; positive testing for HIV, HBsAg, or HCVAb. Hepatitis B vaccination is allowed
  • Abnormal vital signs such as blood pressure, 12-lead electrocardiogram
  • History of alcohol abuse and/or illicit drug use, tobacco use in excess of 5 cigarettes/day or 2 chews/day
  • Blood donation within 60 days
Contacts and Locations
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Information from the National Library of Medicine

To learn more about this study, you or your doctor may contact the study research staff using the contact information provided by the sponsor.

Please refer to this study by its ClinicalTrials.gov identifier (NCT number): NCT05441215


Contacts
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Contact: Pfizer CT.gov Call Center 1-800-718-1021 ClinicalTrials.gov_Inquiries@pfizer.com

Locations
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Belgium
Brussels Clinical Research Unit Recruiting
Brussels, Bruxelles-capitale, Région DE, Belgium, B-1070
Sponsors and Collaborators
Pfizer
Investigators
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Study Director: Pfizer CT.gov Call Center Pfizer
More Information
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Additional Information:

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Responsible Party: Pfizer
ClinicalTrials.gov Identifier: NCT05441215    
Other Study ID Numbers: C4671039
2022-001020-15 ( EudraCT Number )
First Posted: July 1, 2022    Key Record Dates
Last Update Posted: March 13, 2023
Last Verified: March 2023
Individual Participant Data (IPD) Sharing Statement:
Plan to Share IPD: No
Plan Description: Pfizer will provide access to individual de-identified participant data and related study documents (e.g. protocol, Statistical Analysis Plan (SAP), Clinical Study Report (CSR)) upon request from qualified researchers, and subject to certain criteria, conditions, and exceptions. Further details on Pfizer's data sharing criteria and process for requesting access can be found at: https://www.pfizer.com/science/clinical_trials/trial_data_and_results/data_requests.

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Studies a U.S. FDA-regulated Drug Product: Yes
Studies a U.S. FDA-regulated Device Product: No
Keywords provided by Pfizer:
Severe acute respiratory syndrome coronavirus 2 (SARS-Cov-2)
Lactation
COVID-19
Breastfeeding
Protease Inhibitor
Additional relevant MeSH terms:
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Ritonavir
Nirmatrelvir
HIV Protease Inhibitors
Viral Protease Inhibitors
Protease Inhibitors
Enzyme Inhibitors
Molecular Mechanisms of Pharmacological Action
 Anti-HIV Agents
Anti-Retroviral Agents
Antiviral Agents
Anti-Infective Agents
Cytochrome P-450 CYP3A Inhibitors
Cytochrome P-450 Enzyme Inhibitors